Ration



u ,6. o. cuan/IE, 1R. PROCESS FOR PREPABRING'ACETONE FROII/I ACETIC ACID. APPLICATION FILED JUNE-I6. |916. RENEWED'DEC. I2' |917- S2 i u I I I I Il II l |l s En sTNTEs PATENT oEEioE. N

GEORGE o. contra, Jia., or PITTSBURGH, PENNSYLVANIA, AssIeNoN, Br NESNE ASSIGNMENTS, To UNION .OAREIDE COMPANY, or NEW YORK, N. Y., n Conro- RA'TION. OF VIRGINIA.

PROCESS FORMPBEPARIN'G CETONE FROM CETIG ACW.

naissant.

Application led June 16, 1916, Serial No. 104,077.

To `aZZaUwm/z't may concern Y Be it lknown that ll, GEORGE 0. CURME, d r., a citizenV of the United States, residing at Pittsburgh, Allegheny county, and, State of o Pennsylvania, have invented and discovered acertai new and useful Improvements in Processes for Preparing cetone. from Acetic (Acid, of which the following is a speciiication.'A

lt has been known and recognized since the very early days of chemical science that acetone can be produced by the thermal decomposition of acetates, especially the acetates of the alkaline earth metals, or, indeed, by the thermal' decomposition of acetic acid itself, alone or in the presence of certaln `substances exerting catalytic. effect on the vapors of the acetic acid. 'lhe temperature to be used, the vessels required, the` method of heating, catalytic substances in whose presence the reaction runs more smoothly, and many other points influencing the above described reactions, have themselves formed the basis for the granting of patents in thls @t and other countries. 0

Liebig -originally made the observation that acetic acid, when conducted through an iron tube vheated Yred hot, is decomposed, yielding acetone alon with others-products. t@ As is obvious from thls authors publication, v the temperature was not accurately measured nor regulated; also, the yield was far from that demanded by the theory in a reaction running smoothly to give all the ace-- t5 tone possible according-to the reaction Squibb found that acetic acid is decomposed in the presence of certainl alkaline earth l t0 .oXids, carbonatos or acetates to give good` but. not perfect yields of acetone, and subsequently Sabatier, Maihle and others have specified a varietyV of oxids, metals, and compounds'of metals, the presence of which,

N t5 facilitates the smooth decomposition of free acetic acid, in the absence or presence of water vapor, into acetone.

li have discovered that metallic iron can Specication of Letters Patent.

Renewed December 12, 1917. serial No, coatto.

to 5500-600o C., into which the vapors of Patented Sept. 0, lglw.

metallic state but at thesame time brings about the decomposition of the acetic acid into acetone, carbon dioXid and water, with practically no formation of methane, hydrogen or other less valuable substances. The special features of the iron in this case are; first, that being a good conductor of heat it maintains a uniform temperature throughout the tube, a most essential feature of a complete and uniform reaction; second, it does not exert a destructive contact e'ect on the acetone once formed, but permits it to pass on through thetube unchanged to the receivers; third, it does exert a contact e'ect on the acetic acid vapor, permitting the decomposition-which tends to take place anyway-of the acetic acid at a lower temperature than though it were not present; fourth, the combination of effects just mentioned is such that` the transformation ofv the acetic acid to acetone carbon dioXid and water, as p acetone may be repared from acetic acid in the vapor formi y passing the same through tubes or vessels containing iron in'a finely divided condition, as of fine shavings, maintaining these tubes or vessels ata temperaf ture between 550 rC. and 600 C., at which temperaturea quantitative yield of acetone is `obtainedfrom the acetic acid introduced, condensing the vapors issuing from this apparatus and then preparing from the "condensate, by simple rectification, thepure acetone. n

lin carrying out my invention, l use an apparatus of a general character illustrated in the accompanying drawing, wherein 10 represents a still for the acetic acid; 11 a chamber filled with ironshavings and connected with the Still v10 'by a pipe 12; 13 a, con` denser'in which a condensing coil 14 connected with the chamber 11 is mounted, and 15 the acetone container. A heater such as a` gas burner 16, or other appropriate'heating device is mounted under thechamber 11.

The condenser has a cooling medium lnlet 17 and outlet 18.

In' operation the acetic acid vapor passes i through pipe 12, into the heated chamber 11,

which is fllled With comminuted iron and heated, and the heat maintained at a temperaturev approximately as above stated,

which' permits decomposition. The vapors pass from chamber 11 out through the condensing coil 14 Where they are condensed and are discharged into thev container 15.

1. The process of preparing acetone from acetic acid in the form of vapor which consists in lpassing sald` vapor through vessels containin iron in finely' comminuted condi- 25 tion and eated to a temperature approximately between 550 C. and 600. C.

2. The rocess of preparing acetone from acetic aci which consists in mixingacetic acid vapor with the vapors of other liquidsns and passing the mixture over heated iron in a finely lcomminuted condition, substantially as set forth.

3. The process of preparing acetone which consists in mixing acetic acid vapor with 35 Water vapor and `passing the mixture through a re-action chamber in contact with heated iron in finely comminuted condition, substantially as set forth.

In witness whereof, I have hereunto set 40 my hand and seal at Washington, District of Columbia, this twenty-ninth day of May, A. D. nineteen hundred and sixteen. l

GEORGE o. CURME, JR. [La] Witnesses:

E. W. B RADFoRD, CEAS. E. RIORDAN. 

